在複雜微生物組中單一細菌屬維持根系的生長
作者:
小柯機器人發布時間:2020/10/2 23:30:23
美國北卡羅萊納大學教堂山分校Jeffery L. Dangl及其研究小組發現在複雜微生物組中單一細菌屬對於維持根系的生長至關重要。該研究於2020年9月30日在線發表於《自然》雜誌。
在本研究中,為了了解微生物之間的相互作用如何影響擬南芥根的生長,研究人員建立了植物、微生物與環境之間相互作用的模型系統。研究人員將幼苗接種於含185個細菌的合成群落,並操縱非生物環境以及測量植物的細菌定殖。該模型系統使得研究人員可以將合成群落分為四個模塊的共生菌株。研究人員在這些模塊的基礎上解構了合成群落,並確定了決定根表型微生物之間的相互作用。這些相互作用主要涉及單個細菌屬(Variovorax),它完全逆轉了由多種細菌菌株以及整個185個成員群落引起的對根系生長的嚴重抑制。
研究人員證明了Variovorax通過調控植物激素水平來平衡生態上人工合成根系對根系生長的影響。研究確定了生長素降解操縱子,在所有可用的Variovorax基因組中都保守,並且對於逆轉根生長抑制是必要和充分的。因此,代謝信號幹擾會影響細菌-植物間的通訊網絡,並且對於維持根部的發育程序至關重要。優化根系化學相互作用網絡為研發具有高抗災力和高產作物提供了一種潛在的生態策略。
據了解,植物生長在複雜的物種網絡中,這些物種之間以及其與植物之間存在相互作用。這些相互作用受各種化學信號的影響,因此,根系化學信號可以強烈影響根的健康和發育。
附:英文原文
Title: A single bacterial genus maintains root growth in a complex microbiome
Author: Omri M. Finkel, Isai Salas-Gonzlez, Gabriel Castrillo, Jonathan M. Conway, Theresa F. Law, Paulo Jos Pereira Lima Teixeira, Ellie D. Wilson, Connor R. Fitzpatrick, Corbin D. Jones, Jeffery L. Dangl
Issue&Volume: 2020-09-30
Abstract: Plants grow within a complex web of species that interact with each other and with the plant1–10. These interactions are governed by a wide repertoire of chemical signals, and the resulting chemical landscape of the rhizosphere can strongly affect root health and development7–9,11–18. Here, to understand how interactions between microorganisms influence root growth in Arabidopsis, we established a model system for interactions between plants, microorganisms and the environment. We inoculated seedlings with a 185-member bacterial synthetic community, manipulated the abiotic environment and measured bacterial colonization of the plant. This enabled us to classify the synthetic community into four modules of co-occurring strains. We deconstructed the synthetic community on the basis of these modules, and identified interactions between microorganisms that determine root phenotype. These interactions primarily involve a single bacterial genus (Variovorax), which completely reverses the severe inhibition of root growth that is induced by a wide diversity of bacterial strains as well as by the entire 185-member community. We demonstrate that Variovorax manipulates plant hormone levels to balance the effects of our ecologically realistic synthetic root community on root growth. We identify an auxin-degradation operon that is conserved in all available genomes of Variovorax and is necessary and sufficient for the reversion of root growth inhibition. Therefore, metabolic signal interference shapes bacteria–plant communication networks and is essential for maintaining the stereotypic developmental programme of the root. Optimizing the feedbacks that shape chemical interaction networks in the rhizosphere provides a promising ecological strategy for developing more resilient and productive crops. Experiments using an ecologically realistic 185-member bacterial synthetic community in the root system of Arabidopsis reveal that Variovorax bacteria can influence plant hormone levels to reverse the inhibitory effect of the community on root growth.
DOI: 10.1038/s41586-020-2778-7
Source: https://www.nature.com/articles/s41586-020-2778-7